1. Field of the Invention
The present invention relates to a disk drive, and more particularly, to a suspension assembly for to support a slider, on which a read/write head is mounted, and to an actuator for moving the read/write head to a predetermined position of a disk.
2. Description of the Related Art
As one of the information storage devices of a computer, the hard disk drive (HDD) is a device for to reproduce/record data from/on a disk using a read/write head.
Such a hard disk drive includes an actuator to move a read/write head to a predetermined position of a disk. The actuator is provided with: a swing arm; a suspension assembly installed in one end portion of the swing arm to bias, elastically, a slider toward a surface of the disk, in which the read/write head is mounted on the slider; and a voice coil motor (VCM) to rotate the swing arm.
If the hard disk drive is powered on and the disk starts to rotate, the voice mail motor rotates the swing arm to move the slider over a recording surface of the disk. The read/write head mounted on the slider functions to reproduce or record data from/on the recording surface of the disk.
Meanwhile, if the hard disk drive does not operate, that is, if the disk is stopped, the voice coil motor moves and parks the read/write head out of the recording surface of the disk to prevent the read/write head from colliding against the recording surface of the disk. Generally, such head parking systems may be classified into a contact start stop (CSS) system and a ramp loading system. In the CSS system, a parking zone in which data is non-recordable is provided in an inner circumference of the disk and the head is parked in contact with the parking zone. In the ramp loading system, a ramp is installed outside the disk, and the head is parked on the ramp.
FIG. 1 is an exemplary view showing a conventional suspension assembly of an actuator for a disk drive, which is disclosed in U.S. Pat. No. 6,067,209. Referring to FIG. 1, two suspension assemblies are arranged on both sides of a disk 21. One end portion of a flexure 29 is attached to a load beam 28 of the suspension assembly and a slider 30 is attached to the flexure 29 using an adhesive agent. An end-tab 28a is extendedly formed on a front end portion of the load beam 28. The end-tab 28a is supported in contact with a surface of a ramp 24. A first limiter 37 is provided on a front end portion of the flexure 29 and a block member 27 is provided on the ramp 24. In addition, a second limiter 29a is provided between the front end and rear end portions of the flexure 29. The second limiter 29a extends through an aperture 31, which is formed on the load beam 28.
If a vertical shock is applied to the conventional suspension assembly constructed as above, the first limiter 37 contacts with the block member 27 of the ramp 24 and the second limiter 29a is engaged with the load beam 28. Therefore, a movement of the flexure 29 in the pitching direction is limited, thus preventing collision of the sliders 30, which face each other.
Since the first limiters 37 are, however, disposed very close to the sliders 30, the first limiter 37 may collide robustly against the block member 27 if a relatively strong shock is applied to the conventional suspension assembly. The shock is directly transferred to the slider 30, such that the sliders 30 are frequently separated from the flexures 29.
Meanwhile, a crash stop is provided in the disk drive to limit the clockwise and counterclockwise rotation of the actuator. If a horizontal shock is applied robustly to the actuator from the outside in operation of the disk drive, or if a horizontal shock is applied to the actuator due to a collision with the crash stop in a reliability test of the disk drive, the flexures 29 are moved or twisted in the rolling direction. Thus, the sliders 30 may collide against the surface of the disk 21. As a result, the head and the disk 21 may be damaged, or a deformation may be caused, resulting in degradation in read/write performance of the head.
In the conventional suspension assembly, the first and second limiters 37 and 29a may cope with the vertical shock, but cannot effectively cope with the horizontal shock and the resultant twisted deformation of the flexures 29.
FIG. 2 is an exemplary view showing a conventional suspension assembly of an actuator for a disk drive, which is disclosed in U.S. Pat. No. 6,388,843. Referring to FIG. 2, a limiter 70 to limit a movement of a flexure 52 in the pitching direction is provided on both sides of a front end portion of a load beam 51. However, the limiter 70 of the suspension assembly also cannot limit a movement of the limiter 70 in the rolling direction, which is problematic.
Meanwhile, U.S. Pat. No. 6,445,546 discloses a suspension assembly, in which slots are formed on a load beam and tabs bent from a flexure are inserted into the slots. In such a structure, however, an area where a slider is attached to the flexure becomes narrower due to the tabs. Therefore, the slider may be easily separated from the flexure due to an external shock. Further, the assembling process becomes difficult because the tabs must be bent after their insertion into the slots.